8 Appendix E – Multi-Kernel Support

From ATWILC 15.7 onwards, the kernel featurization code is removed. The WILC family releases are based on specific Linux4Microchip kernel releases. To use the latest driver on an older version of the kernel, backporting is required. Refer to the patch shared at wilc_driver_multikernel.patch to backport the driver.

To download, apply and prepare the Multi-Kernel Support patch, perform the following steps:

Clone the Linux kernel from the linux4microchip github repository.
```
git clone https://github.com/linux4microchip/linux.git
```
Check out the required Linux4Microchip kernel, for example, the linux4microchip-2022.04 tag.
```
git checkout linux4microchip-2022.04 -b linux4microchip-2022.04
```
Download the Multi-Kernel Support patch for the specific ATWILC release from files.linux4microchip.com, for example:files.linux4microchip.com/pub/wilc/wilc_16_1/linux/linux-6.1-mchp/linux4microchip-2023.04/wilc_driver_multikernel.patch.
Apply the patch using the following command:
```
git am --3way wilc_driver_multikernel.patch
```
Note: The patch shown in this section applies only to driver versions 15.7-16.1. To support Multi-Kernel in the latest release, users can reference the patch and integrate the changes into the latest driver.